Sixty minutes is one hour, a meeting, a study block, or a bake you should set and then actually heed. An hour is long enough to drift. Write the single outcome on paper before you press start.
There is also a one hour timer if you think in hours. Same length, different page, so the title matches the search. Press space to start or pause, R to reset, and F for fullscreen. The screen can stay awake after you start, using the wake lock your browser allows. Pick the alarm before you begin. A bell, a chime, a beep, or a short digital pulse all come from the Web Audio API, so there is no sound file to wait on.
This page is the 1 hour countdown and nothing else is running underneath it. Related lengths are linked under the guide if you want a neighbor, and the timer itself stays above the fold.
Questions
How do I run a 1 hour timer on a projector?
Press start, then F or the fullscreen button. Classroom mode hides the writing so the digits fill the wall. There is also a one hour timer if you think in hours. Same length, different page, so the title matches the search.
What is 1 hour actually good for?
Sixty minutes is one hour, a meeting, a study block, or a bake you should set and then actually heed.
Will the countdown drift if I switch tabs?
No. The end is a timestamp. The display is the gap between that timestamp and now, so a background tab does not lose seconds the way a ticking counter would.